Carburetor



P. .3. CCJLEMAN CRBURETOR Filed June 1l, i925 2 SheetS-Sheet 1 ATTORNEY.

Patented ld". l ,r Eil Application filled-.Tune 11, 19%. serio?. Ho.@41,521

To ail 'whom it may' concern Be it known that l, PATRICK J. COLEMAN, o.citizen of the United States, residing et Highland Parli, county ofWVayne, State of Michigan, have invented a certain new and usefulImprovement in Carburetors, and declare the following to be a full,clear, and exact description of the seine, such us will enable othersskilled in the art to which it pertains to make and use the seme,reference 'being had to the accoinpenyinff drawings, which form o partof this speci icetion.

rllhis invention relates to carburetors and the object of the inventionis to'provide a cerburetor in which the liquid fuel is mixed with oirrbefore"being passed into the main air conduit. Another object of theinventicnvis 'to provide a carburetor having the 'main air conduit inthe form of e Venturi tube and vinto `vhicb the mixture of air andliquid fuel: is blown at 'the point of greatest restriction. Afurtherobject of the invention is toprovideafcurburetorutilizing an air pumpfor blowing the fuel mixture into the mein air conduit of thecarburetor, the air pump being operated by the engine with which thecarburetor is used and the pressure of the air produced by the pumpbein@ utilized to control the ilovv of the liquid fue into the main airconduit. Another object of the invention is to provide a carburetor inWhich the liquid fuel is mixed With hot air as it is blown into the mainconduit of the carburetor, the hot air assisting in vaporizing the fueles it posses from the jet. A further object of tbe invention is toprovide a means for controlling the flow of fuel into the carburetor,the fuel regulating means being controlled by the pressure of the airpump .which in turn is controlled by the speed of the internal.combustion engine. These objects and the several novel features of theinvention vare hereinafter more fully described and claimed end thepreferred form of construction lby which these objects are attainedisshown in the-accompanying drawings in which- Y Fig. 1 is aside'elevation of an internal combustion .engine showing Iny ,carburetormounted thereon.

Fig-.f2 is en enlarged elevation of the car buretor.

Fig. 3 is a section teken on line 3 3 of Fig. 2.

big. 4 is e longitudinal section throug'h tbe carburetor. l

Fig 5 is e section through the fuel control p Fig. 6 is e sectionthrough an elternative type of fuel control pin.

As shown in Fig. 2 the carburetor cornprises a. bowl 1 connected byineens of e line 2, shown more particularly in Fig. 1, With a liquidfuel supply tank. The level of fuel in the bowl 1 is controlled byineens of e. float 3 which is adapted to open or close the fuel feedline to the bowl 1 by means of a needle valve 4 as is the usualconstruction. Cast integrally with vthe bowl 1 is the main air conduit 5which, es shown in Fig. e, is in the form of a Venturi tube on theinterior and provided with an aree or greatest restriction at 6. Thismain air conduit is controlled b means of a buttery valve which is provied with an operating erm 8 shown in Fig. 2 end which 1s connected bymeans of a rod 9 shown in Fig. 1 with the usual foot or hand throttle.The lower end of the main air conduit 5 is connected b ineens of aflexible conduit 10 sbovvn in ig. 1 to an air chamber about theexhaust..manifold of the .internal combustion engineI and through whichliot air is adapted 'to be 4 drawn into the main air conduit 5. As shownin Figs, 3 and 4 the conduit 5 is rovided With an integral portion 11exten ing across the conduit, the conduit being enlarged about thisportion to revent restric-4 i tion to air flow tberethroug A. recess 12is formed in the conduit on the side opposite the bowl 1 and a piston 13is positioned in the recess 12 and is provided with peclrii'ig rings 14which engage the sides of tbe'recess 12 and with the member 13 form aclosed chamber 15. As 'shown in Fig. 1 an air pump 16 is mounted on theinternal combus tion engine and is adapted to be driven by the internalcombustion engiri'in any 'suitable manner end a pressure linf'e 17extends from the pump l5 and is Wound about the exhaust manifold 18 andis connected at the opposite end to a boss 19 provided on thecarburetor. This boss 19 is provided with en aperture 2O which o ensinto the chember 15 and through Whic i the pressure line 17 into the`seid chamber. -A coiled s ring 21 engages in the member 1B on the si eopposite the chamber 15 and e cap 22 is threaded onto the portion 23 ofthe carburetor about tbe recess 12 and by threading' the cap onto oroli' from the portion 23 the tension of the spring 21 muy be increcsodg'air may dow from or decreased as desired. A member ,24 isV threadedthrough the member 13 and a pack? ing 25 is provided which is held inplace by a packing uut 26 toprevent leakage of airI about the member 24from the chamber' 15.

is rotatable in an annular mem er 32 whichI is made a press fit in theend of the aperture 30, the aperture 36 -being provided with a reducedportion 33 which is open to the bowl V1 of the carburetor.

The end 31 of the member 24 is provided wither tapered groove 34 in oneside thereof as shown more particularly in Fig. 5, and the 'liquid fuelmay flow from the aperture' 33 through this groove 34 into the aperture305- A jet 35 opens into the aperture 30 and extends longitudinally ofthe main air conduit 5' as shown. A deep recess or auxiliary air conduit36 is4 rovided iii the member 11 through which t e-jet 35 extends and atubular umember 37 is p'osi tioned about the jet, one end of thetubulark member opening into the recess 36 and thev o posite end thereofopening` about thediseiarge end of the jet A35. T'his/ recess 361s opento the chamber 15 and is controlled bymearisof a valve 38 seatingtherein, the valve 38/,b'eing provided with an extending end 39 ,asshown in Fig. 3 which may be regulated to control the dow through therecess 36 as will be readily understood.v The piston 13 is providedwitlia pin 40 extending there-f from at one side of vthe member 24 andengages in a recess 4l provided in the portion l1 to prevent the piston.13 from turning'on its llongitudinal axis, the recess 41 being ofsufficient depth to allow longitudinal move'-l inent of the piston.

To start the engine the crank shaftA 42 Y 'thereof is lrotated whichoperates the pump 16 and forces air ythrough the line`17, chamber 15.,auxiliary air conduit 36 and through j the tubular member 37 past thedischarge end of the jet 35 which draws the liquid fuely through the jetinto therniain air conduit of thecarburetoiwhere it is further mixedwith the air passing therethrough and passes about the butterfly valve7l into the engine.

where it` is ignited and the engine is thus started. The yposition ofthe member 13 is l determined by the pressure of air in the chamber 15produced by the pum-p 16. l/Vnon the engine is first started and atidling speeds the pressure is not so great and the The member 13 isforcedto the left of the position shown in Fig.I 4 by the spring21 thuspositioning the deeper part of the groove 34 in the member 32 andallowing a greater How of liquid fuel from the bowl into the aperture 36for idling speeds. As the butterfly valve 7 is opened the speed of theengine is increased which in turn increases the speed of the pump andthe pressure in the chamber 15 and also increases the flow of-aii' fromthe end of the tubula'i""m'cinber\37 which tends to ull the liquid fuelthrough the jet 35 witi ,more force.A As the pressure is vincreased inthe chamber 15 the member 13 is moved to the right against the tensionof the spring 21 until a position is found where it equalizes 4betweenthe'tension of the spring 21 and the pressure in the chamber 15. By thisarrangement the-member 24 is moved to *fthe right which draws the end 31thereof to the right to position'the shallower part of the groove 34 inthe member 32 so that less liquid :fuel is used at the higher speedsforY each explosion of the en ine, but the fuel,4

ydue to ,greater suction is vra'wn through the groove 34 at a greatervelocity; By means of the-handle 28 the member 24'may'be threadedthrough the member 13 to a greater or less extent to regulatetheposition ofthe groove .34 extending through ythe member 32 in relationto the position'of the member 13,

ithe member 24 being calibrated for this pur; pose as shown in Fi 4. y*By n'ieans of this 1 adjustment the liqui fuelsupply may be adjusted sothat the carburetor may be used on engines of differentv horse power and"by I (means of the extending end 39 the. valve -38 may be regulated tovary the flow `vof air about the jet which in turn're latesthe guantitof liquid fuel drawn t rough the )et an valve 38 and member '24 will befound to be about the same for engines of the saine number of cylindershaving the same bore. and stroke. While I have shown in Fi v5 v.a groove34 of a certainshape itA iste-ie unby experiment the setting of theiyderstood that thisinvention is not limited t A this specific shapecofgroove.A For instance as shown .in Fig. 6 agroove 34a 'vided which isdeepest at the and this t supply of extreme end iquid fuel at hi may bepro- 1.151 i pe of groove will give a greater-V gher engine speeds'vwhile the type shown in Fig. 5 will cut down()l the supply of liquidfuel in aiias the engine speed is increased. 'It will be noted by t ieconstructioiiheiein described proportion tothe that when the position ofthe -memberi24is I' set in relation to the member 13 and the posi@ tionof the valve 38 is set in the recess' 36 the.,

entire control'of the carburetoriis accomplished by means of thebutterfiyK valve 2' which .is operated by the throttle adjaceii thedrivers seat, movement of thefvalve Afl* causing the other parts tooperate in relation i thereto and when the engine is shut ofi" the isainsane? i heated as the engine warms upthus aiding Vits utility and modeo o eration, what in vaporizing the liquid fuel as the air passes fromthe tubular member 37. Satisfactory results may be attained however byrunning the line 17 straight to the chamber l5 and not preheating theauxiliary air though somewhat better results may be had by heating thepressure linen F rom the foregoing description it becomes evident thatthe device is very simple and ecient in operation, will not easily getout of order, will automatically adjust itself for dierent engine speedsand may be manually adjusted for engines oi' diiierent horse power.

Having thus fully described my invention claim and desire to secure yilettersatent of 'the United States is l. A carburetor :for an internalcombustion engine, comprising a main air conduit, a chamber provided atthe side thereof, an air pump driven by the internal combustion engine,a pressure line for the air pump discharging into the chamber, a pistonreciprocable in the chamber, a spring yield ably resisting movement Voi"the piston by the air pressure, means for regulating the tension oi' thespring, a iiquid foei supply, a conduit, for the liquid fuel supply, anan-l nular member fitting the conduit, a cylindrical member adjustablein the piston and having a/ cylindrical end fitting in the an nnlarmember, the said end lbeing provided with a longitudinal slot tapered inrelation to the longitudinal axis of the said cylindrical member, a jetin communication with the fuel suppl through the slot of the c lindricalmem er and discharging into t e main air conduit, a. tubular memberabout the jet discharging into the main air conduit at the discharge endof the jet, an auxiliary air conduit allowing dischar e of air from thechamber through the tubu ar member, a valve regulating dow of airthrough the auxiliary air conduit, and a butteriiy valve regulating ilowof air and fuel through the main air conduit.

2. In a carburetor for an 4internal combustion engine, a main airconduit in the I form of a Venturi tube, a ebamber-pi'ovided at the sideof the main air conduit, an air pump driven by the internalA combustionengine, pressure line d i charging into the chamber, a giston recip-,jior the air pump disrocable in the chamber, a sp" ing yieldablyresisting movement of the ,pi ton by the air pressure, means forregulatmg the tension ont the spring, a liquid fuel supply, aiet incommunication with theliquid fuel s upply discharging into the main airconduit at the point of greatest restriction, a tubular member about thejet through which air is discharged from the chamber into the main airconduit, adjustable means controlling discharge of air from the chamberand a member adjustablein the piston and reguiating How of liquid fuelto the jet by movement of the iston.

3. in a car uretor for an internal combustion en 'ne, a main airconduit, a chamber provi ed at the side thereof, anl air pump driven bythe internal combustion engine, a pressure line for the air pump dischar'ng into the chamber, a piston reciproca le in the chamber, anadjustable spring yieldably resisting movement of the piston by the airpressure, a liquid fuel supply, a jet in communication with the liquidfuel supply discharging into the main air conduit, a 'tubular memberabout the jet through which air is discharged from the chamber into themain air conduit, and a member adjustable in the piston and regulatingflow of liquid fuel to the jet by movement of the piston.

e. In a carburetor for an internal combustion engine, a main airconduit,v a chamber provided at the side thereof, an air pump driven bythe internal combustion engine, a pressure line for the air pumpdischarging into the chamber, a piston reciprocable in the chamber, aspring yieldably resisting movement of the piston by the air pressure, aliquid fuel sup ly, ai jet in communication with the liqui fuel supplyand discharging into the main air conduit, a tubular member about thejet through which the llair is adapted to discharge from the chamber,means controlling the discharge of fair through the tubular member, anda meinber carried by the piston controlling ilqw of liquid fuel to thejet.

5. In a carburetor for an internal combustion engine, a main'airconduit, a chamber provided at the side thereof, an air pump driven bythe internal combustion en-l gine, a pressure line for the air umpdischarging heated air into the cham er, a' piston reciprocable in thechamber, a sprmg yieldably resisting movement of the piston by the airpressure, a liquid fuel sup 1y, a jet in communication With the liquiduelV supply and dischargin into the main air conduit, a tubular mem erabout the jet, an air conduit adapted to directair from the chamberthrough the tubular member about the jet, and a member carried bytheplston controlling flow of liquid fuel to the get.

6. In a carburetor for an internal cmbustion en e, a. main air conduifa, member provi ed in the side thereof'ran'ain resisting movement of thepiston by-the an' pressure, means'for adjusting the tension of thesmina'. a. liquid fuel supply, a jet in conmmnication with th'e iiquidfue] supply 10 and discharging into the, main air. conduit., and amember adjust-able'l' longitudinally in the pistn und regulating How ofliquid fue! to he jet by movement f the piston.

In testimony whereuf,A I sign this specifi- 1f? cation.

PATRICK J. COLEMAN.

